Solar Panels save energy costs by absorbing the sun’s rays located in the best places directly exposed to catch and harvest it. Most people think that the hotter the location the better the voltage output for Solar Panels would be and may even be so hot the panels could be a fire hazard. Can Solar Panels Catch Fire?
Yes, Solar panel fires are rare but happen due to hot spots within the system which can be flammable causing arcs between the ground & the conductor creating a fire hazard caused by:
Poorly designed systems
Improperly installed electrical equipment
Faulty products
Over-voltage
Power surges
Lightening
With safer smaller Solar Systems for Off-Grid Cabins and RV’s Solar can come pre-wired and uncomplicated but with bigger systems comes bigger power generators that sometimes need the attention of a person with a little bit more expertise. Solar panel fires are rare. Previous industry reports indicate lower than 1 incident per 10,000 installations.
Do Solar Panels Get Hot
Solar Panels laid across the roof of a house, barn or cabin can keep the sun from beating down on the roof of a structure while absorbing the sunlight and heat into the Solar System but blocking its rays from heating up the inside of the building. This direct heat would have passed through the roof especially if the roof was shingled with asphalt.
Then at night when the temperature cools down the Solar Panels can radiate any heat that built up during the day for a while until dissipates into the cooler nighttime air. Kind of an extra layer of thermal protection. Solar can save you money by increasing a building’s total energy efficiency besides doing what you bought them for, creating energy by using the sun to run the airconditioning that will also keep the structure cool. They can act as a blanket and hold the heat that was built up during the day in the material of the Solar Panel.
The Panels can get pretty hot laying up on your roof all day under direct sunlight. The Panels are made of glass and metal-framed that absorb heat and can get very hot. Home solar panels are tested at 77 °F and thus solar panel temperature will generally range between 15 °C and 35 °C during which solar cells will produce at maximum efficiency. However, solar panels can get as hot as 149 °F at which point solar cell efficiency will be negatively affected.
Install factors like how close the panels are installed to the roof can impact the typical heat of your solar system. But if you are installing them on an off-grid structure, RV, or Log Cabin the chances are you won’t be factoring in the engineered installation instructions used in the factory by the manufacturer. The actual temperatures will change during the summer months with cloud coverage increasing and decreasing outdoors and the material in the panel absorbing constant heat and getting even hotter over time.
Most of the solar energy striking the panel will be absorbed and converted to heat since the silicon cells are typically dark blue and absorptive. The metal framing like all metal objects sitting out directly in the sun will absorb high temperatures. Some of that heat will hold and radiate to the surface below, radiate back to the sky, or be conducted away to the surrounding air.
Solar Panel Fires
Although the record is a good one, a Solar Panel System is very safe as far as a reason for fires go and deemed fairly safe. There are incidents that do happen but are easy to identify why and most can be preventable.
Faulty Defective Connections-Just like any electrical work when installing a Solar System care attention should be practiced. Be on the lookout for faulty connections or cable insulation breakdowns that may induce electrical faults. Electrical faults, like arc faults, short circuits, ground faults, and reverse currents are a risk with all and any type of electrical equipment. If you are installing the equipment for small systems in Off-Grid locations a reasonable amount of knowledge is needed.
In larger solar photovoltaic (PV) systems, multiple solar panels are connected in series in a string to increase the voltage before going to the inverter. Multiple strings of the solar panels are also combined together in parallel to produce higher output currents in what Solar calls a Combiner Box. A solar power combiner box is a device that combines the output of multiple strings of solar panels for connection to the inverter. This reduces the number of wires that need to safely go to the inverter and needs to be connected, checked, or worked on by a Solar Professional or a licensed Electrician.
Then again if you are installing a Home system that is connected to the grid then absolutely use professional Installers that are licensed Technicians that work for a reputable company. There is a huge difference between a Solar System for your RV or Camper and the Systems that are State certified and fully insured. Code enforcement laws and inspections come into effect with the object of homeowners’ protection enforced.
According to the National Fire Protection Association, about 44,000 electrical fires happen in the United States every year. The leading cause of electrical fires is equipment malfunction, especially damaged wiring that causes electricity to an arc. An electric arc is like a mini bolt of lightning. It happens when a spark from damaged wiring or faulty equipment travels through the air into nearby objects. When arcing happens in the walls of your home or near anything combustible, fires can ignite. A Solar fire can start the same way but in reality, the Fires started from Solar systems are very low.
Bad Installation- Installers that are not certified or licensed Technicians, especially on bigger jobs can and do make mistakes without correcting them. This was the reason that CEO Elon Musk of Tesla used when his Solar Panels were used on numerous Walmarts around the Country ended up burning some of them down and creating a huge lawsuit. Walmart claimed, among myriad complaints, that
According to CNBC “Tesla routinely deployed individuals to inspect the solar systems who lacked basic solar training and knowledge.” In the suit, they also alleged that Tesla failed to ground its solar and electrical systems properly and that Tesla-installed solar panels on-site at Walmart stores contained a high number of defects that were visible to the naked eye, and which Tesla should have found and repaired before they led to fires.
Hot Spots- is a small fire risk that can happen in a Solar Panel when a crack or damaged cell occurs, in rare cases, can generate so much heat that it causes flammable materials in or near the panel to catch on fire. A hot spot occurs when a single cell is damaged or is unable to generate electricity while nearby cells continue to generate power.
Due to the way that solar panels are wired, a dead cell can end up carrying the current of neighboring cells, causing it to heat up. Fortunately, all solar panels that you install in your home will have multiple devices called bypass diodes (that are located in the PV Junction Box on the back of each Solar Panel) that prevent the heating effects related to a non-producing solar cell.
All solar panels that you install on your home today will have multiple devices called bypass diodes that prevent power from going through the damaged non-producing cell that alleviates the fire hazard.
- Monitor your system for individual panel issues. If you have microinverters or power optimizers, you will have the instruments to check the power output of individual panels in your system.
- Clean any debris on your panels. In most cases, it isn’t necessary or even recommended to regularly clean your solar panels. Unless you live in a dusty and dry region, periodic rain may be all the cleaning you need.
- Maintain nearby foliage. Not only can nearby trees shade your system and reduce your power harvest, but deciduous trees can drop leaves on your system every fall. If you can, keep your trees trimmed to prevent this annoyance.
How To Cool Solar Panels
Solar panels are generally factory tested at about 77°F and are rated to perform at peak efficiency between 59°F and 95°F. However, solar panels may get as hot as 149°F laid flat on a roof during the summer. When the surface temperature of your solar panels gets this high, solar panel efficiency as strange as it sounds can decline somewhat.
A basic technology employed by most panel manufacturers is to use a thermally conductive substrate to house their panels, which helps vent heat away from the glass layers of the module. Solar panels are also commonly mounted a few inches above a surface, with airflow space below the actual unit, helping to move heat away from the modules and cooling them down as well.
There are Solar Panels with a higher temperature working range if you are living in areas of the country that will be hotter than the normal range on average. They will cost a few extra bucks. Like the top quality Top Solar Flexible Solar Panel 200W 18V 12V Semi-Flex SunPower Cell Thin Lightweight Solar Panel Charger with MC4 Connector for RV Boat Cabin Tent Yacht Car Uneven, Surfacessold here through Amazon take a look.
Misting water over the front of the panel can cause mineral build-up, letting de-io water run down the front of the panel and then catching it to fill up a water heater passive solar techniques, but still, need pump power. Rainwater that has no minerals and is collected can be used when the panels get too hot at midday in the summer. You can use airspace if your panels are not attached to your roof. If the array of panels is not laying flat then air from a fan that is powered by the Solar panels can be used.
JimGalloway Author/Editor
References: Hot Spot Heating
EnergySage– Effect of temperature on solar performance
